U.S. patent application number 13/698471 was filed with the patent office on 2013-03-07 for twin-clutch for a twin-clutch variable speed transmission in motor vehicles.
This patent application is currently assigned to AUDI AG. The applicant listed for this patent is Hans-Peter Fleischmann, Mathias Jakob-Bodenhagen, Tassilo Scholle. Invention is credited to Hans-Peter Fleischmann, Mathias Jakob-Bodenhagen, Tassilo Scholle.
Application Number | 20130056323 13/698471 |
Document ID | / |
Family ID | 44118804 |
Filed Date | 2013-03-07 |
United States Patent
Application |
20130056323 |
Kind Code |
A1 |
Jakob-Bodenhagen; Mathias ;
et al. |
March 7, 2013 |
TWIN-CLUTCH FOR A TWIN-CLUTCH VARIABLE SPEED TRANSMISSION IN MOTOR
VEHICLES
Abstract
A twin-clutch for a twin-clutch variable speed transmission in
motor vehicles includes two wet running multi-disk-clutches which
are arranged axially in succession in a transmission housing,
wherein end walls of the transmission housing are provided on
respective sides of the multi disk clutches, a driving clutch
housing; two transmission hubs outputting to transmission input
shafts, and alternately drivingly connectable with the clutch
housing via clutch disks; ring pistons shiftably supported in the
end walls of the transmission housing and hydraulically
pressurizeable with pressure oil via ducts arranged in the end
walls to thereby cause a shifting of the ring pistons, wherein the
ring pistons alternately act on the clutch disks via pressure
disks, and wherein the pressure disks are actuatable from outside
the clutch housing by the ring pistons; and axial rolling bearings
respectively arranged between the ring pistons and the pressure
disks.
Inventors: |
Jakob-Bodenhagen; Mathias;
(Gaimersheim, DE) ; Fleischmann; Hans-Peter;
(Stammham, DE) ; Scholle; Tassilo; (Ingolstadt,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Jakob-Bodenhagen; Mathias
Fleischmann; Hans-Peter
Scholle; Tassilo |
Gaimersheim
Stammham
Ingolstadt |
|
DE
DE
DE |
|
|
Assignee: |
AUDI AG
Ingolstadt
DE
|
Family ID: |
44118804 |
Appl. No.: |
13/698471 |
Filed: |
May 18, 2011 |
PCT Filed: |
May 18, 2011 |
PCT NO: |
PCT/EP2011/002471 |
371 Date: |
November 16, 2012 |
Current U.S.
Class: |
192/48.603 |
Current CPC
Class: |
F16D 25/10 20130101;
F16D 25/082 20130101; F16D 2021/0692 20130101; F16D 2021/0661
20130101; F16D 21/06 20130101; Y10T 74/19228 20150115 |
Class at
Publication: |
192/48.603 |
International
Class: |
F16D 25/10 20060101
F16D025/10 |
Foreign Application Data
Date |
Code |
Application Number |
May 19, 2010 |
DE |
10 2010 021 036.6 |
Claims
1. -15. (canceled)
16. A twin-clutch for a twin-clutch variable speed transmission in
motor vehicles, comprising: two wet running multi-disk-clutches
which are arranged axially in succession in a transmission housing,
wherein end walls of the transmission housing are provided on
respective sides of the multi disk clutches; a driving clutch
housing; two transmission hubs outputting to transmission input
shafts, and alternately drivingly connectable with the clutch
housing via clutch disks; ring pistons shiftably supported in the
end walls of the transmission housing and hydraulically
pressurizeable with pressure oil via ducts arranged in the end
walls to thereby cause a shifting of the ring pistons, said ring
pistons alternately acting on the clutch disks via pressure disks,
said pressure disks being actuatable by the ring pistons from
outside the clutch housing and; axial rolling bearings respectively
arranged between the ring pistons and the pressure disks.
17. The twin-clutch of claim 16, wherein the clutch housing is
drum-shaped and securely connected with the drive shaft via a
central hub and is constructed to have one open side, and wherein
the two multi-disk-clutches and the two pressure disks are
insertable into the clutch housing from the open side.
18. The twin-clutch of claim 17, wherein one of the pressure disks
which faces toward a closed end side of the clutch housing is
actuatable from outside the clutch housing with radially inward
protruding arms through corresponding recesses in an end wall of
the clutch housing.
19. The twin-clutch of claim 16, wherein the ring pistons have ring
sections which have an L-shaped cross section, and wherein the
axial rolling bearings are guided on the ring sections.
20. The twin-clutch of claim 16, wherein the ring pistons have a
U-shaped cross section and carry ring cuffs which surround the ring
pistons, wherein the ring pistons are inserted into annular
groove-shaped recesses of the end walls in a liquid tight manner,
and wherein the ducts lead into said annular groove-shaped
recesses.
21. The twin-clutch of claim 20, wherein the ducts are configured
for supplying cooling-oil.
22. The twin-clutch of claim 16, wherein surfaces of the pressure
disks with which the pressure disks contact the pressure rings of
the axial rolling bearings are ring shaped or interrupted in a
circumferential direction, and are configured to have a spherical
cross section
23. The twin-clutch of claim 16, further comprising return springs
for separating the clutch disks, wherein the clutch discs are
alternately formed by steel discs and drive discs provided with a
friction lining on both sides, said drive discs being connected in
circumferential direction with the transmission hosing or the
transmission hubs in a from fitting manner, and wherein the return
springs are arranged radially inside or outside of the friction
linings.
24. The twin-clutch of claim 23, wherein the return springs are
formed by disk springs.
25. The twin clutch of claim 23, wherein the return springs are
formed by corrugated disks.
26. The twin-clutch of claim 16, wherein the two transmission hubs
are formed by ring parts which have an L-shaped cross section, and
wherein a radial flange of the transmission hubs is securely
connected to hollow shaft sections of the input shafts of the
variable speed transmission.
27. The twin-clutch of claim 16, wherein a respective axial rolling
bearing is arranged between adjacent connection flanges of hollow
shaft sections of the input shafts and between a connection flange
of a drive shaft which protrudes into the clutch housing and is
fixedly connected with a central hub of the clutch housing.
28. The twin-clutch of claim 16, wherein the drive shaft has an
extended section which extends past a connection flange for the
central hub, and wherein a respective radial rolling bearing is
inserted between said extended section and the hollow shaft
sections.
29. The twin-clutch of claim 28, wherein an outer one of the hollow
shaft sections is connected to a further extending hollow input
shaft of the variable speed transmission via a plug-in gearing and
wherein a corresponding radial rolling bearing is arranged in a
region of the plug-in gearing and in a corresponding one of the end
walls of the transmission housing.
30. The twin-clutch of claim 16, wherein a radially inner one of
the hollow shaft sections is connected with a radially inner one of
the transmission input shafts of the variable speed transmission
via a plug-in tooting and is additionally guided in the extended
section of the drive shaft via a radial rolling bearing.
31. The twin-clutch of claim 16, further comprising a disk spring
inserted between a radially outer one of the hollow shaft sections
and a further extending input shaft of the variable speed
transmission, said disk spring axially pretensioning the radially
outer hollow shaft section against the drive shaft.
Description
[0001] The invention relates to a twin-clutch for a twin-clutch
variable speed transmission in motor vehicles according to patent
claim 1.
[0002] Such a twin-clutch with two multi-disk-clutches which are
positioned axially adjacent one another is disclosed in DE 101 46
606 A1, in which a drum-shaped clutch housing as driving clutch
element encloses two clutch hubs which are coupled via clutch
disks, which clutch hubs are in driving relationship with two
coaxial input shaft of the variable speed transmission. Such a
transmission arrangement enables a symmetrical construction of many
clutch elements by using identical components which are
advantageous for manufacture. The multi-disk-clutch is actuated
hydraulically by means of ring pistons which are integrated inside
the clutch housing and the clutch disks which are pressurized via
ducts in the input shafts of the transmission. This requires a
significant sealing and manufacturing effort for effective control
of the multi-disk-clutch and as the case may be for supplying the
multi-disk-clutch with cooling oil.
[0003] DE 10 2005 027 467 A1 discloses a further device for the
transmission of rotational torques which includes a positionally
fixed piston and a rotatable engaging plate. The rotatable engaging
plate is arranged adjacent to a rotatable housing and separated
from the housing by a return spring arrangement. In a pre-loaded
state, the return spring arrangement is nested between the engaging
plate and the rotatable housing.
[0004] The object of the invention is to propose a twin-clutch
which has a robust construction and whose hydraulic actuation and
as the case may be, supply with cooling oil is simpler and easier
with regard to manufacture.
[0005] This object is solved according to the invention by the
features of patent claim 1. Advantageous refinements are set forth
in the further patent claims.
[0006] According to the invention, it is proposed that the ring
pistons are shiftably supported in end walls of the clutch housing
provided on both sides of the multi-disk-clutches, and supplied
with pressure oil via ducts arranged in the end walls, and that a
respective axial rolling bearing is arranged between the ring
pistons and the pressure discs which are pressurized from outside
the clutch housing. Appropriate constructing of the clutch housing
and the use of a rolling bearing for each multi-disk-clutch allows
reconfiguration of the clutch actuation so that sealing elements
which are exposed to relative rotations (for example piston rings)
are not required and corresponding supply ducts and sealing
arrangements in the transmission input shafts are not needed. The
pressure-oil and optionally, cooling-oil supply can be achieved via
supply ducts which are integrated in the clutch housing, and
enables an improved pressure-oil supply with corresponding direct,
sensitive actuation of the transmission.
[0007] Particularly advantageously, the drum-shaped clutch housing
can be fixedly connected to the drive shaft via a central hub and
configured open on one side, wherein the two multi-disk-clutches
and the two pressure discs are insertable and the outer pressure
disc can be correspondingly actuated from the open side.
[0008] Further, the pressure disc of one of the multi-disk-clutch
which faces toward the closed front side of the clutch housing can
be actuated from outside with radially inward protruding arms
through corresponding recesses in the end wall of the clutch
housing. This allows actuating the multi-disk-clutches from both
sides via their pressure discs in spite of a central drive of the
clutch housing.
[0009] In a structurally and constructively simple manner, the ring
pistons can have ring sections with an L-shaped cross section, on
which ring sections the rolling bearings are guided. The ring
sections can preferably be molded directly to the ring pistons.
[0010] Further, the ring pistons which have a U-shaped cross
section can carry ring cuffs which surround the ring pistons, and
be inserted in a liquid tight manner in ring groove shaped recesses
of the end wall of the clutch housing, into which the ducts for the
supply with pressure-oil and optionally cooling-oil also lead. For
the cooling oil, outlet openings can be provided which may be
controlled via the ring pistons.
[0011] Further, the ring-shaped, or in circumferential direction
interrupted, surfaces of the pressure discs which contact the
pressure rings of the axial rolling bearing can be configured
spherical in cross section in order to create a low-wear
introduction of force from the pressure rings into the pressure
discs.
[0012] In a particularly advantageous refinement of the invention,
the clutch disks can be alternately formed by steel disks and drive
plates which have a friction lining on both sides, which drive
plates are connected to the clutch housing or the clutch hubs in
circumferential direction in a form fitting manner, wherein
radially outside or inside the friction linings, ring shaped return
springs are arranged which separate the clutch disks, and are
configured as plate springs or corrugated disks. The return springs
of the proposed type enable a fast and yet particularly sensitive
control of the clutch torques in the multi-disk clutches, which is
par.sub.ticularly advantageous in twin-clutch transmissions due to
the partially overlapping torque transmission.
[0013] Manufacturing-wise and functionally particularly
advantageously, the two clutch hubs can be formed by ring elements
which have an L-shaped cross section, and whose radial flanges are
connected with hollow shaft sections of the input shafts of the
variable speed transmission. In addition to the mounting advantages
resulting there from when assembling the twin-clutch, the clutch
hubs can be manufactured as extrusion parts of same geometry and
can constructively advantageously be integrated into the clutch
housing.
[0014] The further patent claims describe a particularly
advantageous rolling bearing of the clutch elements which are
connected to the transmission shafts with a support which is to the
greatest degree relieved of bending moments even at high torque
transmissions.
[0015] In the following, an exemplary embodiment of the invention
is explained in more detail with further details. The schematic
drawing shows in:
[0016] FIG. 1 in a longitudinal section the upper half of a
twin-clutch for a twin-clutch variable speed transmission in a
motor vehicle with two multi-disk clutches; and
[0017] FIG. 2 a section of the multi-disk clutches of one of the
multi-disk clutches with inserted corrugated disc as return
spring.
[0018] In FIG. 1, 10 designates a twin-clutch for a not shown
twin-clutch variable speed transmission for motor vehicles, which
is arranged in a clutch housing 12. A housing section 12a which
encloses the twin-clutch 10, and a housing cover 12b are mounted
inside a clutch case (not shown) to the clutch housing 12 or its
end wall 12c.
[0019] The twin-clutch 10 has two wet-running multi-disk-clutches
K1 and K2 which are arranged inside a drum-shaped clutch housing
14.
[0020] The driving clutch housing 14 is formed by a radial inner
central hub 14a, a radial flange 14b and an outer cylinder 14c. The
central hub 14a further has an inwardly protruding flange section
14d which is fixedly connected to a connection flange 16d which is
molded to a drive shaft 16 and extends radially outwardly.
[0021] The drive shaft 16 is, in a manner which is not shown, for
example via a rotational swinging muffler or a two mass swinging
wheel, connected to the crank shaft of an internal combustion
engine and drives the clutch housing 14 of the twin-clutch 10.
[0022] The drive shaft 16 is rotatably supported in the housing
cover 12b via an axially and radially guiding ball bearing 18
(four-point bearing) and sealed against the outside by means of an
inserted shaft seal ring 20.
[0023] Inside the clutch housing 14, the two driven clutch hubs 22,
24 of the multi disk clutches K1, K2 are arranged which are each
formed by ring parts which have an L-shaped cross section, and
whose radially inward protruding flange sections 22a, 24a are
connected with connection flanges 26a, 28a of hollow shaft sections
which are arranged coaxially to one another.
[0024] The inner hollow shaft section 26 is drivingly connected
with a first input shaft 32 of the variable speed transmission via
a plug-in gearing 30, wherein a projection 32a of the input shaft
32 with a small cross section protrudes into a section 16b of the
drive shaft 16 which is extended via the flange section 16a and is
rotatably supported in a rolling bearing arranged there
between.
[0025] The outer hollow shaft section 28 is drivingly connected to
the second input shaft 38 via a further plug-in gearing 36, wherein
a radial rolling bearing 40 which interacts with the input shaft 38
is arranged in the region of the plug-in connection, and is
inserted into a bearing receptacle of the end wall 12b of the
clutch housing 12.
[0026] Between the two hollow shaft sections 26, 28 and between the
extended section 16b of the drive shaft 16 and the inner hollow
shaft section 26, two further radial rolling bearings 42, 44 are
arranged which ensure a rigid support of the clutch elements and
the transmission shafts.
[0027] Further, axial rolling bearings 46 are provided between the
radial flanges 26a, 28a of the hollow shaft sections 26, 28 and
between the flange section 16a of the drive shaft 16 and the radial
flange 26 which is directly adjacent the flange section 16a, and
the drive shaft 16, which axial rolling bearings 46 support the
axial forces and axial torques which occur at the clutch elements.
A disc spring which is arranged between the outer hollow shaft
section 28 on a ring shoulder 28b and on the front side of the
further extending input shaft 38 of the variable speed transmission
exerts a defined pretension on the axial rolling bearings 46, which
excludes play.
[0028] As can be seen from FIG. 1, the mentioned radial rolling
bearings 34, 40, 42, 44 are formed by needle bearings; the same is
true for the axial rolling bearings 46.
[0029] Incorporated into the outer cylinder 14c of the clutch
housing 14 which is open on one side, and on the transmission hubs
22, 24 are axially parallel grooves (without reference signs), into
which steel disks 48 (see enlarged section according to FIG. 2) and
steel drive disks 50 which carry friction linings (hatched) as
clutch disks alternately protrude in circumferential direction.
[0030] The friction linings on the drive disks 50 are configured so
as to be radially outwardly set back, and corrugated disks are
inserted into the ring shaped intermediate spaces formed thereby,
which corrugated disks act as return springs or push the clutch
disks 48 50 apart in the open state. Instead of the corrugated
disks 52, disk springs can also be used.
[0031] The multi-disk clutches K1, K2 (FIG. 1) are mounted from the
open side of the clutch housing 14, wherein as can be seen, the
multi disk clutch K1 is inserted first with a radially inwardly
extending pressure disk 54 and thereafter, as shown, the clutch
disks 48, 50 and finally a stop disk 51.
[0032] Then, a ring shaped separation element 56 is securely
inserted into the outer cylinder 14c of the clutch housing 14 which
ring-shaped separation element 56 functionally separates the two
multi-disk clutches K1, K2 and for example is held pushed-in and/or
axially unmovable via securing rings.
[0033] Thereafter, the multi-disk clutch K2 is mounted in reverse
order and connected to its pressure disc 60. With the mounting of
the clutch discs 48 50 the mentioned corrugated discs are of course
also inserted (not shown in FIG. 1 for reasons of better
clarity).
[0034] While the pressure disk, which is on the right side in FIG.
1 covers the open side of the clutch housing 14, arms 54a which are
radially inwardly molded onto the left pressure disk 54, (for
example three arms--not visible in the sectional drawing) extend
through corresponding recesses 14e in the end wall 14b of the
clutch housing 14 toward the outside.
[0035] The hydraulic actuation of the two multi disc clutches K1,
K2 occurs via ring pistons 62 on both sides which are arranged
axially shiftable in ring grooves 64 of the end wall 12c of the
clutch housing 12 or in the transmission cover 12b. The ring
pistons 62 which have a U-shaped cross section are covered with
rubber elastic sealing cuffs 62a and are inserted into the ring
grooves in a liquid tight manner.
[0036] The hydraulic pressurization of the ring pistons 62 occurs
via ducts 12d provided in the transmission cover 12b and the end
wall 12c, which ducts 12d are connected to a not shown transmission
control with corresponding control valves and a source for pressure
means. At the same time these ducts 12d can serve for supplying
cooling-oil to the clutch housing 14, with corresponding outlet
openings.
[0037] Ring sections 62b which have an L-shaped cross section are
molded to the ring pistons 62, on which ring sections 62b pressure
bearings or axial rolling bearings 66 are held. The axial rolling
bearings 66 which are configured as ball bearings, act with their
free pressure rings 66a on spherically configured contact surfaces
54b, 60b of the pressure disks 54, 60 of the two
multi-disk-clutches K1, K1. The mentioned contact surfaces 54b of
the left pressure disk 54 are not ring-shaped as in the case of the
right pressure disc, but rather distributed across the
circumference on the arms 54a of the pressure disk 54.
[0038] When one of the multi-disk clutches K1, K2 is to be closed,
the corresponding ring piston 62 is pressurized with pressure-oil
via the transmission control, so that the corresponding pressure
disk 54, 60 compresses the clutch disks 48, 50 and the corrugated
disks 52 via the axial rolling bearing 66.
[0039] As a result, torque is increasingly transferred from the
drive shaft 16 and the clutch housing 14 via one of the
transmission hubs 22, 24 to one of the input shafts 32, 36 of the
variable speed transmission.
[0040] When the twin-clutch 10 is to be switched, the multi-disk
clutch (for example K1) which is closed at his point, is opened and
almost without interruption of the pulling force, the other
multi-disk-clutch is closed. The return force of the used
corrugated disks 52 ensures a fast opening of the then inactive
multi-disk-clutch (K1)
* * * * *